Airbrush device



AIR BRUSH DEVI GE June 4, 1946. J. A. PAASCHE 2,401,504

AIR BRUSH DEVICE Filed Dec. 4, 1943 2 .Shees-Sheef. 2

IN VEN TOR.

tented Jane si, 1946 UNITED vSTATES PATENT OFFICE AIRBRUSH DEVICE Jens A. Paasche, Chicago, Ill.

Application December 4, 1943, Serial No. 512,846

3 Claims. ll

The present invention relates to spray or air brush devices and more particularly to an improved air brush device adapted for applying hot or cold protective coatings.

The present invention is particularly concerned with improvements in spraying or air brush devices for the application of protective coatings such as heavy oils, parailins, greases, asphalt compounds, glues, resins, waxes, et cetera, which must be heated so as to be in a fluid state of a desired viscosity so that the material sprayed may be properly atomized. In spraying` such materials it furthermore is desirable to maintain the sprayed material at a temperature or viscosity so that the material will adhere and cohere properly on the object to be coated. Accordingly, the present invention contemplates a device which heats the material to be sprayed and means are provided for supplying a heated aeriform substance to atomize the material being sprayed and to envelope such sprayed material with an atmos' phere which does not cool or materially reduce the desired viscosity of the material. In the application of certain materials it furthermore may be found desirable to use in place of air, such as is the common aeriform substance used, some other gas which would prevent oxidation of the sprayed material.

It therefore is an object of the present invention to provide an improved spraying device as set forth above, wherein electrical heating means are provided which are thermostatically controlled to obtain the desired temperatures of the aeriform substance and the material to be sprayed'.

A still further object of the present invention is to provide an air brush device of the type set forth above which is readily supported in one hand and which is provided with suitable control devices whereby the desired rate of flow and pattern of spray may be controlled.

Other and further objects will subsequently become apparent by reference to the following description taken in connection with the accompanying drawings, wherein:

Fig. 1 shows a perspective side view of the apparatus comprising the present invention;

Fig. 2 is a partial cross-sectional view of the apparatus shown in Fig. 1;

Fig. 3 is a view along the line 3-3 of Fig. 2; and

Fig. 4 is a view in the opposite direction from Fig. 3 along the line 4-4 of Fig. 2.

Referring more particularly to Fig. 1 of the drawings, it will be seen that there has been provided a spraying apparatus having a material container or chamber, such as II, which may be cylindrical in form as shown and provided with a cover I2 which may be securely fastened in position on the chamber II by suitable fastening means I3.- Such suitable fastening means I3 may comprise a member having two clamping ears, such as I4, connected to an intermediate supporting Structure I5 which is provided with a threaded aperture wherein a screw member I6 may be arranged to operate by a handle member I'l. The entire assembly is conveniently held in one hand by holding a handle 49 which is connected to a spraying mechanism I 9 interposed between a handle 49 and the material chamber II. A spraying apparatus I9 is controlled by a trigger 2| which operates certain valve mechanisms controlling the ow of an aeriform substance and material to a nozzle assembly 22 mounted at the front of the spraying mechanism I9. The nozzle 22 through suitable valve mechanism is arranged for communication with the material passage 23 interconnecting a material chamber II and a spraying apparatus I9; and also with an aeriform substance under pressure which is supplied through a suitable hose or conduit 24. The hose or conduit 24 is connected through suitable coupling means 25 to a point adjacent a lower portion of the material chamber II.

Immediately below the material chamber II there is another chamber 26 of slightly greater diameter wherein there is provided a circuitous aeriform passage 20. Suitable heating means are provided for heating both the aeriform passage 20 and the material chamber II so that heated material and a heated aeriform substance may be supplied simultaneously to the spraying apparatus I9. The temperature of the chamber II is controlled by a suitable thermostat 21 mounted beneath the lower chamber 26. Electric power is supplied through a suitable connecting cord 28 and a plug assembly associated with the apparatus in the vicinity of the thermostat 2l.

of the aeriform passage 29 there is mounted a heating element 9| provided with a pair of electric terminals I2 and 99 which are joined by suit- `able conductors 94 and 95 to the thermostat assembly 21. The thermostat assembly 21 may comprise any suitable thermostat arrangement well known in the prior art. 'I'he lower chamber 29 is supported from the bottom of the upper material chamber Il by a. stud 39 mounted adjacent the central portion of the bottom of the upper chamber Il. The other extremity of the stud 29 is threaded so as to receive a nut 91 which bears against an insulating plate 99 positioned adjacent the bottom of the lower chamber 29. On the inside of the lower chamber 29 there are provided a plurality of spacing members 39 and 4I above which is mounted the heating element 9i which is positioned between two suitable supporting plates 42 and 43. The upper supporting plate 43 is retained in position by a corrulated plate 45 provided adjacent its center with a collar portion 49 which is threaded at the interior so as to engage the threaded portion of the stud 99. The threaded collar portion 49 together with the nut I1 therefore operate to retain in position the various elements between the fiber plate 99 and the upper corrugated supporting plate 45.

The spraying apparatus I9 comprises a forward portion or nozzle assembly generally indicated by the numeral 41, a central body portion 49 which carries the nozzle assembly 41 and a handle 49 by which the body portion 49 may be supported. Material from the chamber Il is introduced in the nozzle assembly 41 through a passage 5l formed of an angularly upstanding portion 52 in the frame 49 and interconnected by a suitable coupling member 59 which threadedly engages the member 52 and a threaded opening adjacent the bottom of the material chamber Il. The angularly disposed material passage 52 joins with a horizontal passage 54 having supported therein a centrally disposed needle member 55 which cooperates with an orifice 55, The needle 55 passes through a bearing portion 51 in the body 49 and through a packing chamber 59 containing suitable packing rings and a spring for holding the packing rings in compressed position. Just beyond the packing member 59 the needle 55 is secured to a longitudinally movable member 9|, The rear extremity of the needle 55 is supported in a suitable bearing surface 92 formed in the frame 49. Interposed between the bearing 92 and the longitudinally movable member 9| is a spring 99 which urges the needle 55 forwardly against the orice 59. The longitudinally movable member Il extends horizontally and downwardly through a suitable opening 94 in the frame 49 and upwardly to be secured to a longitudinally movable rod 95 mounted in a suitable bearing in the frame 49. The rod 95 is provided at its rear end with a. reduced portion arranged to engage a recess in a valve member 99 which cooperates with a valve opening 91 in the frame 49. At an intermediate point adjacent that portion of the longitudinally movable member 9| which extends through the opening 94 there is provided an elongated slot arranged to cooperate with a pin 99 mounted in a handle lever 99. The handle lever 99 is pivotally mounted adjacent its upper end by a suitable pin 1I. The lower extremity o! the handle lever 99 may be enclosed by a suitable gripping member or casing 2l. An angular displacement of the lever 99 toward the rear causes the pin 99 to engage the slot in the member 9i, thereby to produce a rearward longitudinal motion which moves the needle 59 away from the orifice 59 and at the same time moves the valve 99 away from the valve seat 91. The valve 99 is biased toward closure by a suitable spring 13 mounted between the valve 99 and an end cap 14 which is secured to the frame 49 by a coupling member 15. 'I'he end cap 14 is secured to the lower extremity of the aeriform passage 29.

The aeriform passage 29 which is united with the end cap 14 therefore communicates with a passage 19 in which the spring 13 and the valve 69 are positioned. When the valve 99 is moved rearwardly from the seat 91, communication is had between the passage 19 and another passage 11 which extends forwardly to an annular passage 19 which is in communication with a plurality of longitudinal passages 19. Some of the passages 19 are also arranged for communication with another passage 9i in which there is mounted a valve member 92 which cooperates with a valve seat interconnecting a pair of passages 93 and 94. The passages 93 and 94 are in comorifice 99 which surrounds the material orifice 59. The nozzle assembly 41 is arranged to be demountable for ready cleaning by a suitable clamping ring 99 provided about its periphery with suitable protuberances or knurlings. In order to provide access to the packing chamber 99 for renewing the packings, a forward portion of the gun may be separated by uncoupling the coupling 53 and by loosening a clamping ring Il. 'I'he packing rings then may be removed and renewed.

In order to control the proportion of air or an aeriform substance supplied to the passages 99 and 94 and the cooperating ports 95 and 99, the valve 82 is arranged to be adjustable. The valve head 92 is mounted on a threaded stem 92 terminating in a. knob 93. The knob 93 is locked to the stem 92 by a cooperating lock nut member 94 so that the knob 93 and the lock nut member 94 are moved as a unitary assembly. The valve head 92 together with the stem 92, the knob 99 and the lock nut portion 94 are mounted within a nipple or housing 95 formed integral with the central body portion 49 of the spraying apparatus. The nipple or housing 95 engages at its outer extremity a plug-like threaded member 99. the interior of which is also threaded to engage the threads on the valve stem 92. Suitable packing and a spring are interposed between the head 92 of the valve assembly and the threaded member plug 99. Thus by rotation of the knob 99 the position of the valve head 92 may be set so that a predetermined amount of the air supplied through the spraying apparatus will be projected from the ports 95 and 99 to give the desired fanning effect.

The main frame or body l49 of the spraying apparatus is provided adjacent its rear portion with a downwardly angularly projecting member 91 which is threaded on its interior so as to be engaged by a bolt or threaded tubular member 90 having at the other extremity a head or nut |00 which secures in position the handle 49. Interposed between the handle 49 and the main frame 48 of the spraying aparatus is a heat insulating member 99 arranged so that when the heated aeriform substance passes through the spraying apparatus for any appreciable amount of time, the heated body of the spraying apparatus will not come in contact with the operators hand. For the same reason the handle-like portion 2| on the trigger lever 69 may also be formed of a suitable heat insulating material. In order to regulate the degree of movement of the lever 69, the handle 49 is provided adjacent its upper portion with an adjusting screw |0| having a threaded portion arranged to engage a suitable threaded opening |02 formed in the handle. 'I'he adjusting screw |0| is provided with a coiled spring |03 arranged to retain the screw in adjusted position. Extending forwardly of the knurled nut-like portion |0| of the adjusting screw is a stud |04 which engages the rear of the handle 2|, thereby to limit the degree to which the valve head 66 and the needle valve 55 are moved from their respective cooperating seats. The flat insulating plate 38 interposed between the lower chamber 26 and the main body 48 of the spraying apparatus further assists in insulating the spraying apparatus from the heat generated by the heating element 3 I. i

From the above description of the apparatus it therefore becomes apparent that there has been provided a unitary assembly which is readily supported in one hand of the operator by the handle 49 and the operation thereof controlled by actuation of the lever 69. It thus will be appreciated that the cord 28 is connected to a suitable electrical outlet to supply electrical energy to the heating element 3| which energy is controlled in accordance with the setting of an adjustable thermostat assembly 21. A suitable gaseous fluid, such as air, is connected to the hose 24 to supply an aeriform substance to the passage wherein the substance will be heated to the desired tem-c perature. The material such as asphalt, grease, or other protective coating contained within the material chamber is heated so as to be in a :duid state with the desired degree of viscosity. After the apparatus has been heated for a suftlcient length of time, the handle 2| is actuated slightly to permit a. passage of the aeriform substance through the spraying apparatus to bring it to proper operating temperature. Thereafter the handle 2| may be actuated to its fullest extent so as to clearly open the material passage by the withdrawal oi the needle 55 from the port or orifice 56. The material which leaves the nozzle assembly from the orice 66 is surrounded by .o

6 heated aeriform substance projected through the orifice 88 so as to surround the material and to atomize it. The particular pattern desired in the formof atomized material is controlled by the ports and 86. The material to be applied to an object to be coated, therefore, is projected in atomized form in an atmosphere which envelopes it and maintains it at a predetermined temperature so as to obtain good adherence and coherence v of the material particles to the object to be coated and to each other. The heated aeriform substance prevents the material from becoming cooled prior to the application to the object to be coated and where desired the aeriform substance may be of such a nature as to prevent oxidation of the material being applied.

After the apparatus has been placed in operation it frequently is necessary to interrupt the spraying operation to handle the work or perform other duties. In order that the apparatus will not cool off so as to bring about a congestion of the heated material passage, the valve 66 is provided with a fine slot 10 or hole so that a small amount of heated air is permitted to escape, thereby to keep the head and body portions of the gun heated.

While the particular embodiment of the invention has been disclosed, in order to readily explain the invention it, of course, will be understood that I do not wish to be limited thereto since obviously modifications and alterations may be made in the instrumentalities employed and in their arrangements without departing from the spirit and scope of the invention as set forth in the appended claims.

The invention is hereby claimed as follows:

l. In a sprayer for viscuous material, a nozzle, a container for the material to be sprayed, means providing communication between said nozzle and said container,- an electric heating element positioned adjacent an exterior surface of said container, a heat exchanger coil, means positioning said coil in juxtaposition with said exterior surface of said container between said surface and said'heating element, means for supplying a gaseous fluid under pressure to said heat exchanger coil, a passage providing communication between said heat exchanger coil and said nozzle, said heat exchanger coil being formed with an unobstructed area of such extent that proper heating of both the viscuous and the gaseous fluid is simultaneously effected.

2. A sprayer as in claim 1 in which said surface is the bottom of the container.

3. A sprayer as in claim 1 in which said surface is the bottom of the container and in which said nozzle is that of a paint gun and said container is positioned above the paint gun.

JENS A.V PAASCHE. 

